1. Field of the Invention
The present invention is generally related to automobile control systems, and applications of the same. More specifically, the invention is related to a volume control for an automobile turn signal indicator.
2. Background Art
Automobile turn signal indicators utilize flashing lamps on the outside of the automobile to warn surrounding traffic of a prospective change in direction. To indicate a turn, the driver moves a lever that is mounted on the steering wheel, which activates the respective turn signal indicator and causes the corresponding exterior lamps to blink on-and-off. Conventional turn signal indicators also include lamps on the dash board that blink on-and-off in synchronization with the blinking of the exterior lamps. Additionally, an audible xe2x80x9cclickingxe2x80x9d sound is often produced that is also synchronized with the blinking of the exterior lamps. The dash board lamps and audible clicking sound are meant to inform the driver that a particular turn signal indicator is activated. When the driver makes a sufficiently wide turn, a mechanical control device automatically deactivates the turn signal indicator, and stops the blinking lamps and the audible clicking sound.
A problem with conventional turn signal indicators is that occasionally the driver will activate the turn signal, and then not complete the turn for some reason. Alternatively, the driver may execute a turn that is not wide enough to automatically deactivate the indicator, as often occurs when changing lanes during highway driving. When this occurs, the driver must manually deactivate the turn signal indicator in order to stop it. If the turn signal indicator is not manually deactivated, then the driver travels down the road with a blinking turn signal, when no turning maneuver is immediately planned.
As mentioned above, the dash board lamps and the audible clicking sound are supposed to notify the driver when a turn signal indicator is activated. The dash board lamps can be ineffective because the driver""s visual attention is often focused on the road ahead, especially during highway driving. The audible clicking sound is difficult to hear for those drivers that are hearing impaired. Additionally, the audible clicking sound can be drowned-out by traffic noise or the radio, even for those drivers with good hearing.
Therefore, what is needed is a way to improve the effectiveness of the turn signal indicator so that drivers, including hearing impaired drivers, will realize when a turn signal indicator is activated.
The present invention is directed at a volume control for an automobile turn signal indicator. The volume control allows the driver to raise or lower the volume of the clicking sound that is produced when a turn signal indicator is activated. As such, the driver is able to increase the volume of the audible clicking sound when operating in a environment having high background noise (i.e. a radio or traffic), or when the driver is hearing impaired.
In embodiments, a thermally sensitive switch connects/disconnects a power supply voltage to the indicator lamps when the driver activates a turn signal lever. The thermally sensitive switch generates an audible clicking sound that is the result the switch action. A microphone receives the clicking sound and generates a corresponding electrical signal. A variable gain amplifier amplifies or attenuates the amplitude of the electrical signal according to the desired volume that is determined by the user/driver. Finally, a speaker converts the electrical signal back into an audible clicking sound that is re-broadcast into the driver compartment.
An advantage of the invention is that the driver is able to raise or lower the volume of the clicking sound, by increasing or decreasing the gain of the variable gain amplifier. Therefore, hearing impaired drivers can increase the volume of the clicking sound as necessary, and decrease the likelihood that they will drive around with an unintended blinking turn signal.
In an alternate embodiments, two or more thermally sensitive switches are configured so that the switches produce clicking sounds of varying sound volume. The driver then selects a switch based the desired volume. For example, low, medium, or high selections could be provided.